Young black women prone to gain more unhealthy abdominal fat than Hispanics, study shows

Black women ages 20 to 29 have increased amounts of unhealthy abdominal and visceral fat than Hispanic women the same age, and young women of both age groups have more as compared to their elders, according to researchers from Wake Forest University Baptist Medical Center and colleagues.

The new research shows that accumulation of abdominal fat that increases risk of type 2 diabetes is greatest in young adulthood for blacks and Hispanics, said endocrinologist Kristen G. Hairston, M.D., M.P.H., lead author of an article published online June 1 by the American Diabetes Association. The study is the first to look at a large minority cohort using computed tomography (CT) scanning to measure longitudinal changes over time in visceral and subcutaneous adipose tissue, which are different types of abdominal fat.

The study followed 389 blacks and 844 Hispanics ages 20 to 69, men and women, grouped by age in 10-year increments. The researchers took baseline measurements of visceral adipose tissue (VAT) and subcutaneous abdominal tissue (SAT) from 1999 to 2002 with follow-up measurements in 2005-2007. VAT is fat that resides within the abdominal cavity around internal organs and has been linked to metabolic disturbances. SAT is the kind of fat that one can pinch, like 'love handles.'

The study found that the young adult age group (ages 20 to 29) had the largest five-year increase in measured adiposity, or fat, regardless of race or gender. The increase in VAT averaged 18 and 12 square centimeters (cm2) among young black and Hispanic women, respectively, and 13 and 7 cm2 among young men. The five-year increase in (SAT) was 89 and 53 cm2 among young black and Hispanic women, respectively, and 76 and 30 cm2 among young men. In general, fat accumulation declined in the older age groups. Abdominal fat accumulation, particularly the visceral type, is significant because previous studies show that VAT changes of this magnitude differentiate those who develop diabetes from those who don't.

Until this study, this pattern of excessive abdominal fat accumulation in young adults has not been reported using CT-measured 'fat depots.' The findings, however, are consistent with several other studies that used measurements such as body mass index and waist circumference. In this study, abdominal tissue area was measured at the L4/L5 vertebral region by CT.

"Our data may help to further identify unique populations at risk for type 2 diabetes and those for whom behavioral intervention might be most effective," said Hairston, assistant professor of endocrinology and metabolism.

Grants from the National Institutes of Health funded the research. The article, titled "Five-year change in visceral adipose tissue quantity in a minority cohort: The IRAS Family Study," appears online. It will be published in the August issue of Diabetes Care, a publication of the American Diabetes Association.

Co-authors include Capri Foy, Ph.D., Orita McCorkle, B.A., and Lynne Wagenknecht, DrPH, from Wake Forest Baptist; Ann Scherzinger, Ph.D., and Jill Norris, M.P.H., Ph.D., from University of Colorado-School of Health Sciences; Anthony Hanley, Ph.D., from University of Toronto, Nutrition Sciences; Steven Haffner, M.D., M.P.H., University of Texas-Health Science Center at San Antonio; and Michael Bryer-Ash from University of Oklahoma School of Health Sciences.